What the buyer is actually specifying
The ACS580-01-034A-4: The two numbers that decide which motor it can carry are the 34 A normal-duty rating and the 27 A heavy-duty rating — the 25 Hp / 20 Hp headline is just the conversion of those currents at 480 V, so panel sizing and cable ampacity track the current figures, not the horsepower label. Supply window is 380-480 V AC three-phase, output is three-phase to the motor, and the enclosure is a wall-mount NEMA 1 package on an R3 frame: 20.93 in tall, 8.16 in wide, 9.33 in deep, which is what governs the cabinet cut-out and the cooling clearance above the drive.
Duty-class split is the real selection lever
Because the part carries two distinct current ratings on the same nameplate, the application drives the call: a fan or centrifugal pump on a flat load curve fits the 34 A normal-duty ceiling; a conveyor, mixer, or any load with high starting torque and frequent cycling lives under the 27 A heavy-duty ceiling, even though the 480 V supply window stays the same. If the driven machine sits between those two profiles, the safe move is to size off heavy duty — the drive will deliver full 25 Hp normal-duty current on a lighter load, but the inverse (running a heavy-duty load off the normal-duty rating) trips on the I²t limit during acceleration.
Panel-side fit and the BOM line
On the panel side, the R3 frame (20.93 in H × 8.16 in W × 9.33 in D) is the cut-out that has to be reserved, and the NEMA 1 wall-mount rating means it expects an indoor, relatively clean enclosure environment — not a rolling-mill pulpit or a washdown bay, where the ACS580-01-034A-4 would be the wrong enclosure class from the start. Because the supply is 380-480 V AC three-phase, the feeder upstream needs the breaker coordination and SCCR evaluated against the drive's own input current, not against the motor's full-load amps — the drive only draws what the motor demands under the active ramp profile, and that gap is what the site electrical engineer reconciles on the single-line.
Sourcing posture
The ACS580-01-034A-4 is specified into the BOM as the 25 Hp / 20 Hp 480 V slot; quotes are run against the RFQ on this order code against the confirmed 34 A / 27 A duty split, with the R3 frame carried through the cable schedule and the cabinet drawing.